Safety hook



ly 17, 1951 c. K. GARRISON 2,561,017

SAFETY HOOK Filed July 8, 1949 35 2 4%.; INVENTOR.

Patented July 17, 1951 UN l TED? STATES PATEN F Fl CEv SAFETY HOOK Charles. K; 'Ga-rrison, Chicago, "IlL, .assignort to; Chicago Steel Foundry Company, Chicago, 111., a corporationof Maine Application July-'8, 1949, :Serial No 103;665

1 The-present invention relates-to an improved and strengthened safety lifting .hook of the type commonly used with cable tackle in thehoisting of heavy loads.

It-is an object 'of'the present'invention toxprovide" a safety "hook: of the foregoing type charactcrizcd'by a factor of safety'which" is substantially greater-than that: of existing hooks of the same generalvtype.

A more specific objectis atoprovidexan improved safety hook: construction including :a cable a connectedclevisuand a lifting hook pivotally mounted on'.- the:clevis, in. which the free-lip orxbill of said hook is en'gageable: withuan integral. crossbar. of saidriclevis to partially sustain theload on .the hook, ...and. incwhich improved provisions are made whereby the pivot whichconnects the hook to the clevis is relieved-of shearing stress imposed by the load.-

.It is another specific object of the invention to provide a safety hookfla'ssemblyof the sort referred to in:.which saidclevis element andhook element are movably connectedby a sliding or floating, pin and slottype, pivotal connection and have coacting, abutting surfaces" which are engageable with one anotherr in' the operativeload sustaining position of.. thexclev-is "and hook elements, and: inwhicha slug. and. socket arrangement on said elements positively resists any tendency of the hook to rotate or shift laterally relative to the clevis after being properly seated against the latter, the engagement of the hook and clevis seating surfaces serving to relieve the above mentioned, pin and slot pivotal connection of said hook and the clevis from shearing stress.

A still further object is to provide an assembly as described in the preceding paragraph in which the lug and socket arrangement is self-cleaning.

Yet another object of the invention is to provide a safety hook construction of the type referred to above which is adapted to be produced at a relatively small cost, since it eliminates comparatively costly machining operations, and may be fabricated of relatively inexpensive castings, rather than forgings, without loss of strength or load bearing capability, in fact with increased strength.

The foregoing statements are indicative in a general way of the nature of the invention, but other and more specific objects will be apparent to those skilled in the art upon a full understanding of the construction and operation of the device.

A single embodiment of the invention is presented herein for purpose of illustration, but it 2' Claims. (Cl; 24-'-232) 2 will be appreciated that'the invention-is susceptie ble ofincorporation in other modified forms com-,- ing within the scopeof the appendedflo'lamis.

In the drawings,

Fig. l is a view' in. vertical; longitudinal section through the .hook' construction, approximately-along'line l-| ofFig. 2;

Fig. 2 is a rear view of the hookassembly lllu's 'trated' in'Fig; 1;

Fig. 3 is a fragmentary view in verticalcross section along a line generally corresponding to line 3--3- of Fig. 4, illustrating-in solid and dotted lines 'the action of the hook element in engaging and disengaging the load sustaining" seat and locking slot of the clevis; and

Fig. 4 is a fragmentary view in section along'a line corresponding to line 4-4 of Fig 3, further illustrating details and relationships of the piv oting parts of the structure.

Referring to the drawings, the'referencenw meral In generally designatesthe clevis of the safety hook, this clevis being fabricated of'a onepiece, heat treated-steel casting; cludes-'- a forwardly and downwardly "projecting portion-I l constitutedby a pair of parallel arms l2 which are integrally connected at their outer, downturned ends by a transverse crossb'ar- 1,3. This crossbar is shaped" to provide an upwardly spacing, concave, hook engaging keeper seat ll. The clevis is provided with an intermediate heel 15 at which the arms I2 are of thickened cross section and are otherwise specially shaped for the purposes to be described. Upwardly of said heel l5 the clevis ID has a bail I6 adapted to be engaged by a cable or other piece of tackle to suspend the hook and its load.

The hook element of the assembly is generally designated I 8. It is provided with a forwardly and upwardly curved bill or tongue I9 terminating in a rounded nose 2!] which is enga-geable with the keeper seat M of the clevis crossbar I3. The shank 2| of hook element I8 is thinned or flattened somewhat in section at 22 (see Figs. 1, 2 and 4) intermediate the curved body portion 23, which is of rounded section, and the relatively thick boss 24 which is formed at the upper, pivoting end of the hook shank. Said boss is provided with a vertically elongated slot 25 which slidably receives a transverse pivot pin 25 carried by the clevis in adjacent the heel l5 thereof.

This thickened clevis heel is shaped to provide the pairs of inwardly projecting, laterally spaced abutments 21, 28 there being a pair of said abut- Clevis In inments on each of the clevis arms 12 at the clevis heel. The spacing of the respective abutments from one another provides a vertically extending slot 29 on either clevis arm [2, as illustrated in Figs. 1, 3 and 4. Abutments 28 extend upwardly at the rear of the clevis heel to provide rear guide elements 28' for the boss 24 in seating and unseating'the hook on the clevis. 1 I

The upper surfaces of the abutments 21, 28 are shaped to provide downwardly and forwardly inclined load receiving surfaces 30. adapted to coact with similarly inclined surfaces 3| which are formed on the bottom of the thickened boss 24 of the hook shank; Integral lugs.

32 are formed on and extend downwardly from said hook boss 24 on either side of the shank 2!. These lugs are receivable in the respective vertical slots 29 of the clevis heel when the hook I8 is in operative position as illustrated in solid lines in Figs. 1, 2 and 4'. It will be noted that said slots 28 extend entirely through the clevis heel IS in the vertical direction to prevent foreign matter, dirt, etc., from accumulating and thus preventing full seating of hook IS on clevis II].

In use, the hook I8 is adapted to be lifted upwardly and swung rearw-ardly from the solid line position of Fig. 3 to the dotted line of that figure to disengage the hook from the clevis for the reception of the load. The parts are then reengaged the hook tongue i9 being engaged in the clevis keeper seat [4 and the lugs 32 of boss 24 allowed to drop down in the respective clevis slots -28.- The respective pairs of abutments 21 and 28 engage said lugs to hold the hook and clevis against relative rotation in this position and the respective surfaces 30 and 3| of said abutment members 21, 28 and boss 24 engage to sustain the loadadjacent the heel of the clevis. The selfcleaning nature of slots 29 insures that this engagement will take place uniformly at all times without requiring attention. The load is thus removed from the pivot pin 26, so that there is These are 4 acterized by a clevis and a hook element floatingly mounted on said clevis by a connection enabling vertical translational shifting and pivotal swinging of said hook element on said clevis, in which said clevis is provided with a vertically extending socket positioned in vertical alignment with said connection and said hook element is provided with a lug disposable in and removable from said socket by said vertical translational movement, thereby to enable said pivotal swinging of said hook element when the lug is removed from the socket, said socket extending through the material of the clevis and being open at the top and bottom to render the same self-cleanin said clevis and hook element having abutment surfaces laterally adjoining said socket and lug respectivelyv which are in vertical load transmitno likelihood of failure of the latter under shear, V

.and is distributed over a relatively wide area, re- ,ducing the stress on the hook boss and clevis abutments. I

' I claim: I v

' 1. A safety hook construction of the type charting engagement when said lug is operatively disposed in said socket. h

2. A safety hook construction of the type characterized by a clevis element and a hook element floatingly mounted thereon by a connection enabling vetical tanslational shifting and pivotal swinging of said hook element on said clevis element, in which said clevis and hook elements are provided with a vertically extending lug and-a lugreceiving socket positioned in vertical alignment with said connection; said lug and socket being defined by vertically extending abutmen'ts on ad jacent surfaces of said respective elements, said lug being removable from said socket by. said vertical translational movement,- thereby to enable said pivotal swinging of saidhook element, said clevis and hook elements having abutment. sur-' faces of substantial area laterally adjoining said socket and lug respectively, which surfaces are in vertical load transmitting engagement when said lug is 'operatively disposed'in said socket. 5

CHARLES K. GARRISON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 2,462,965 Henderson Mar. 1, 1949 

